Tara Costa of Bethpage, who lost 155 pounds on a 2009 edition of NBC's "The Biggest Loser" to finish third, is in a legal dispute with a Levittown-based fitness company.

Costa and FC Online Marketing, which owns the franchise ilovekickboxing.com, have filed lawsuits against each other over issues of in-person appearances, signing with an alleged competitor, use of her likeness and most significantly, says the company's chief, her weight.

"We hired Tara Costa in 2011 to be a spokesperson," Michael Parrella, chief executive of FC, told Newsday. "She came on at a certain weight. We had a fitness clause. She was in material breach after she gained, in my opinion, about 45 pounds. She was supposed to visit 15 of our franchise locations, but we weren't able to send her anywhere because she gained a lot of weight."

Parrella additionally said Costa had signed with the gym franchise Anytime Fitness while she was still with FC, and had not fulfilled contractual social-media obligations.

Darren Heitner, Costa's Miami-based attorney, said his client sued FC, alleging breach of contract over appearance fees and unauthorized use of her name and likeness on ilovekickboxing.com.

Her suit, filed in Florida, was withdrawn there in order to be refiled shortly in New York.

"Ms. Costa hasn't gained weight," he told Newsday. "If that were true and if the public realizes this, then why did they continue to use her image?"

Heitner denied that Anytime Fitness was a competing company.

As for appearances, he said, "My client was willing, available and actually excited to fulfill the terms of the appearance contract. It was no one's fault but FC Online's that those appearance opportunities were not presented to her."